Dredging machinery.



No. 635,270. Patented Oct. I7,v |899.

E. A. BIX & P. B. DONAHOO. DREDGING MACHINERY.

(Application led Apr. 19, 1898.)

(No Model.)

wil; neo/sea :Afrnr Fries.

EDVARD A. RIX AND PETER B.

DONAIIOO, OF SAN FRANCISCO,

CALIFORNIA.

'DREDGING MACHINERY.

SPECIFICATION forming part of Letters Patent N o. 635,270, dated October1'7, 1899.

Application filed April 19 To all whom, it may concern:

Be it known that we, EDWARD A. Rix and PETER B. DONAHOO, citizens of theUnited States, residing at San Francisco, county of .San Francisco, andState of California, have invented certain new and useful Improvementsin Dredging Machinery; and We hereby Our improvement consists in avessel or barge, hereinafter called the pontoon,7 on which the machineryand apparatus are supported, conveyed, and adjusted, capable o f beingmoored by ordinary 'means and in working free from all disturbingstrains in a horizontal plane and provided with a wellway to receive apneumatic caisson and devices to raise and lower the same. It alsoconsists in motive power, air-compressing and Water-impelling machinery,means for raising and expelling excavated material by introducing airinto the uptake'or spoil pipe and by the inductive action of a jet ofwater impelled by a pump, with various accessories that make up anorganized plant or apparatus for subaqueous dredging on a new andimproved method, as hereinafter more particularly explained by aid ofthe drawings herewith and forming a part of this specification.

The especial objects of our invention are to explore for and secure goldin auriferous deposits and also other minerals or valuables, natural orartificial, that are submerged and inaccessible to observation from thesurface and not available by the ordinary methods of dredging.

Referring to the drawings, Figure I represents in elevation andpartially in section a side view of an organized plant and apparatus forsubaqueous dredging and exploration constructed and operating accordingto our invention. Fig. II is a transverse section 1898.SerialNo.678,ll7. (Noniodel.)

showing the elastic lateral supports for the pneumatic caisson.

In the lodgment of sedimentary and alluvial materials, especiallyfluvial deposits, the particles are arrested by their gravity andobstruction. Gold having a specific gravity of eighteen and theparticles being of rugged contour, the latter seek the lowest points,lodging in fissures or crevices on a rugged bottom or in the lowestpoints on the bed-rock when that is bared, so that only a small portioncan be secured by the ordinary methods employed in subaqueous dredgingeven with suction apparatus, because the velocity of the intake IioWfalls off immediately beyond the i ntake-oriiice and ceases to beeffective within a short distance therefrom. Therefore the onlyeffective means of securing gold from subaqueous deposits is by visualexploration,

the same as is practiced above water or in what is calledplacer-working.7

The object of our invention is to supply the same methods below thewater-level, consisting, essentially, in expelling the water from thesurfaces to be explored, so as to admit of visual and manual working onthe bottom and especially over areas that have been dredged by ordinarymeans.

In carrying out our invention we employ mainly wellknown devicesarranged in a peculiar and novel manner with special reference to thework to be done,employin g therefor a floating vessel or pontoon l,preferably quadrangular in form, having an open wellway 2 formedtherein, through which a sealed pneumatic chamber 3, hereinafter calleda caisson, can be lowered to the. bottom 4 of a river or other body ofshallow water where valuable deposits do or are supposed to exist. Thecaisson 3 is supported vertically by means of a strong frame 5, steppedon the back of the pontoon and braced, as seen iu the drawings, andprovided with pulleys G, over which pass sustaining ropes or chains.Lateral support of the caisson 3 is provided for by means of the elasticbearings shown in Fig. II, preferably four in number, consisting ofbearingblocks 42, springs 43, and screws 44. This permits rocking orother motion of the pontoon l without disturbing the caisson 3 when itrests on the bottom 4 and also introduces a IOO degree of flexibilitynecessary in structures of this kind. These chains or ropes 7 afterpassing over the pulleys (3 are led to a drumwinch 8, driven by asteam-engine or other suitable motor and adapted by winding right orleft to raise or lower the caisson 3, as occasion may require.

To force the caisson downward against the bottom 4 or through alluvialmatter resting thereon, there are employed hydraulic or screw jacks 9,that abut against an adjustable cross-beam 10 at the top and a movablecrossbeam 11 at the bottom, the latter resting on springs 12, that bearon the lugs 13, riveted to the top of the caisson 3, so that by meansofthe hydraulic or screw jacks 9 the caisson 3 is forced downward toform a close joint at the bottom or to cut through silt or any loosematerial thereon. The downward pressure thus imparted is equalized bythesprings 12, that permit some motion of the pontoon 1 without affectingthe caisson 3. This downward strain upon the caisson 3 exerts an equalupthrust upon the frame 5 and upon t-he pontoon 1 and with the bearingsshown in Fig. II tends to anchor and hold the pontoon in a iixedposition laterally, as will be understood.

The caisson 3 is divided transversely into two compartments-a workingchamber 14 and an air lock-chamber 15, the latter entered by a door 17,that when shut is sealed against escape of air from the chamber 14. Froman air-compressing engine 1S a pipe-line 19 leads to the two chambers 14and 15 of the caisson 3, where air under pressure is admitted by thevalves 20 and 21 to either chamber or to both, as will be hereinafterexplained.

Steam for motive power is furnished by a steam-boiler 22. A pump 23 isprovided to supply the boiler 22 and for other purposes.

24 is an electric dynamo for lighting the chambers 14 and 15 and forother purposes and is driven by a small engine 25.

2G is a centrifugal pump, the purpose of which will be presentlyexplained.

Other details will be described in connection with the manner ofoperating, which is as follows: The pontoon 1 is moved to the desiredposition and moored, if necessary, and the caisson 3 lowered by means ofthe winch 8 until it rests upon the bottom 4, as seen in the drawings.The cross-beams 10 and 11 are adjusted and pressure is applied by thescrew or hydraulic jacks 9 sufficient to balance the weights of thewater that rises within the chamber 14. Air under pressure is admittedto the working chamber 14 until the water therein is expelled therefromand air begins to escape at the bottom. The workmen then enter thechamber 15, and after closing the door at 17 air is admitted to thischamber by the valve 2O until there is an equilibrium of pressure in thetwo chambers 14 and 15. By opening the door 45 workmen can then descendthrough the hatehway 27 and by a ladder 28 to the bottom, the interiorof the chamber 14 and the bottom at 41 being brilliantly lighted by anelectric lamp 29, as indicatedin the drawings. At the bottomexploitation and working can be carried on the same as upon dry ground,with the advantage that the compressed air in the chamber is employed toraise and expel water and all kinds of comminuted material-such as silt,sand, and gravel-in the manner presently explained. On the workmen goingout they ascend into the chamber 15', the door 45 is shut, andcommunication is closed between the chamber 15 and the working chamberbelow. The valve 20 is then closed, and the one 30 is opened, so thecompressed air will escape from the chamber 15 down to the atmosphericpressure, and a door 17 at either the top or side of the chamber 15 isopened for exit.

In the case of solids, such as boulders that have to be removed from thechamber 14, these can be raised by ordinary tackle to the chamber 15 andtaken from there through the door 17, or the caisson 3 can be slightlyraised, so that boulders or other solids can be pushed out beneath it.

For all kinds of spoil that can be raised and expelled by entrainment ofwater we provide an uptake-pipe 31, having an inlet-nozzle at 32 andflexible suction-pipe 40. As no iiow will take place through this pipeby means of the air-pressure in the chamber 14, such pressure being onlyequal to the hydrostatic head of water around the caisson 3, we admitair to this pipe 31 by means of cocks 33,which air mingles with waterand spoil and reduces the gravity on the well-known method of pneumaticwater-raisin g apparatus.

In case the induction of air into the pipe 31 is not suilicient to raisethe spoil of a heavy or adherent nature we provide water-inductionapparatus consisting of a pump 26, a pipe 34, an ejecting-nozzle 35,that forces water through the pipe 31 on the well-known principle ofejector-nozzles employed for like purposes in open air. With theexception that air may be introduced through the cocks 33 and minglingwith the Water and spoil lightens it, it thus renders the ejector actionof the pump more efiicient. A valve 36, easily accessible to theworkmen, is provided to regulate the iiow through the uptake-pipe 31.

Vhen the induction or ejector method is employed to raise the water andspoil in the pipe 31, the material is drawn through a suction-hose 40from a sump 41, as shown in the drawings. In the other case the bottomend of the pipe 31 can form the inlet for spoil. The pipe 3l dischargesinto the hopper 37, from Where the water and spoil are conducted to aflume 38, provided With gold-catching devices to the rearof the pontoon1,and are dis` charged at 39, as indicated in the drawings.

It will be understood that the spoil sent up through the pipe 31 can betreated by various methods for the extraction of minerals. W'e

have shown the most simple form-that of a Iiume in which riii'ies andquicksilver can be placed.

IIO

IZO

It will be understood that most of the Various elements or parts thatenter into our invention existed in other combinations and directed toother purposes, and while we do not claim these separately or in othercombinations and operating under different conditions,

We do claim as our inventionl. In subaqueous dredging and exploringapparatus, a iioatin g pontoon a wellway therethrough and a pneumaticcaisson suspended therein, means to raise and lower the caisson, screwor hydraulic apparatus to force the caisson downward, and springsinterposed between the hydraulic or screw devices, to maintain an equalpressure around the pontoon, substantially as specified.

2. In subaqueous dredging and exploring apparatus, a floating pontoonand wellway therethrough, a pneumatic caisson suspended in the wellway,means to raise o r lower the caisson and to force it downward, andelastic bearings or abutments between the sides of the pontoon andwellway, so the pontoon may rock or move without disturbing the caisson,substantially as specified.

3. In exploring and dredging apparatus, a oating pontoon on which theoperating parts are mounted, a double-chambered caisson adapted to belowered from the pontoon to the bottom of a stream or other waters, inwhich the .pontoon is moored, means to fill the caisson with air underpressure and expelthe water therefrom, a spoil-pipe extending upward andoutward from the bottom of the caisson provided with an inlet or inletsfor air that will mingle with the water and spoil that ascends the pipe,substantially as specified.

44L. In subaqueous dredging apparatus, a floating pontoon, a pneumaticcaisson mounted thereon, means to raise, lower and force downward thecaisson, means to expel the water therefrom, a spoil-pipe extendingupward and outward from the bottom of the caisson, an air-inlet in saidspoil-pipe, an inductionnozzle discharging into said spoil-pipe, and arotar5T pump, forcing water through said induction-nozzle into saidspoil-pipe, substantially as specified. Y

5. In subaqueous exploring and dredging apparatus, the combination of aoating pontoon, a pneumatic caisson, a gallows-frame to support thecaisson, and means to raise and lower the same, a spoil-discharging pipefromthe bottom of the caisson, extending upward and outward to theexternal air, air-inlets at the lower portion of the discharge-pipe andin combination therewith an induction-nozzle at and discharging into thelower end of the discharge-pipe, arranged and operating substantially asspecified.

6. In dredging and exploring apparatus, a iioating pontoon, anopen-bottomed caisson suspended therefrom, means to raise and lower thelatter, and means to expel the air therefrom, a discharge for water andspoil leading from the bottom of' the caisson to the open-air inlet orinlets, and an induction-noz- Zle for water and a flexible suction hoseor pipe through which the spoil is drawn, substantially as specified.

E. A. RIX.

PETER B. DONAHOO.

\Vitnesses:

H. SANDERsoN, JAMES L. KING.

